


just pull the trigger, i'll take the blame

by yinngoh



Series: Simpler Days [2]
Category: Haikyuu!!
Genre: Alternate Universe - Supernatural Elements, Alternate Universe - Werewolf, Angst, Come Inflation, Demon Oikawa Tooru, Dubious Consent, Implied Mpreg, Knotting, M/M, Werewolves, just a teeny bit of angst don't worry
Language: English
Status: In-Progress
Published: 2016-12-25
Updated: 2017-05-25
Packaged: 2018-09-12 03:11:29
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,893
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9052858
Author URL: https://archiveofourown.org/users/yinngoh/pseuds/yinngoh
Summary: This story relates to my "and the world was gone" from this series. Supposed to be the climax/ending but I've lost motivation to continue with that one for now (whereas I'm always down for sexy times lel).If you haven't read that yet, you just need to know that Oikawa is a very-old demon who de-aged his looks for fun and ended up enjoying his 'new life'. He is not aware of any other supernatural beings (though some are meant to be revealed in later chapters of ATWWG) but himself for at least 2 centuries.Oikawa and Iwaizumi are in university here, both got into Todai (Tokyo U) with different courses and live together.





	1. Chapter 1

**Author's Note:**

> Honestly this is pretty much pure porn lol. I have been lacking Iwaoi content and also this particular buildup/climax scene is pretty much the reason I wrote ATWWG in the first place.
> 
> Disclaimer: I don't own Haikyuu, nor the characters, just the plot (is there any?)  
> P.S. Title is from 'Bad Intentions' by Digital Daggers

He had gotten Iwaizumi completely smashed, but there was still time to back out. Oikawa raked his gaze over his best friend’s unsteady posture sitting on the edge of the bed with second thoughts.  
  


               “Hey, Oikawa,” said friend slurred, lips lifting in a crooked grin. “I’m glad we got to stay together even after school.” Oikawa’s eyes widened. “I thought you’d leave me behind because I wasn’t continuing with volleyball but… I was happy that we managed to get into the same university, even if we’re gonna have to go our own ways eventually.”  
  


Biting his lip, Oikawa released a deep breath and turned blazing eyes to Iwaizumi. “Iwa-chan…” he snaked a hand behind the other’s neck. “ ** _Iwaizumi… maybe we could deepen our relationship a bit more?_** _”_  
  


He knew, even as he laced the words with persuasive magic, that Iwaizumi’s personality would become distorted by suggestion, however little, after this. But Oikawa didn’t think he would survive this any more. _Just give me this one memory. After this, I can let him move on, I can let him go. I can return to how it was before. How_ my life _was before._

* * *

Oikawa gripped tight fingers around Iwaizumi’s shoulders, moaning hesitantly as Iwaizumi’s thick fingers stretched him out, already three fingers in. He pulled away from the kiss to pant, “that’s enough already, just…”  
  


Seeing Iwaizumi glancing around for a moment, Oikawa blinked in comprehension before pulling the other’s gaze back to him as he intoned, “ ** _just like this_** ”. Iwaizumi blinked once, before abandoning his previous search for a condom. He gripped his length, already slicked with precum and the lube already on his hand, and lined himself up with Oikawa.  
  


Slowly, he pushed past Oikawa’s entrance. “Ahh—mnn…” Oikawa’s eyes fell shut as he shuddered, relishing in the stretch and attempting to burn the moment into his memory. When Iwaizumi was fully seated, Oikawa wriggled impatiently before Iwaizumi took the hint and established a slow rhythm.  
  


               “ ** _Iwaizumi, let me—_** ” Oikawa trailed off. He wanted to hear Iwaizumi’s voice. _But what things would he say whilst under my spell?_ He ignored the sharp pain that sparked in his chest at the thought. _Not things_ my _Iwaizumi would truly say_.  
  


His breath was coming short from the guilt and sorrow already consuming him now, and he screwed his eyes shut to try to shake it and focus on the moment. It was the only one he would risk, after all. Memory tampering was dangerous enough done once.  
  


Oikawa let his mind go blank and abandoned his shame as he wrapped his arms around Iwaizumi’s neck, moaning softly and wrapping his legs around Iwaizumi’s hips, urging him on. Iwaizumi’s thrusts were coming faster, harder and Oikawa was drowning in the sensation of being filled like this.  
  


He had taken many lovers in his lifetime, male and female, but he had never assumed the receiving role. But for Iwaizumi… he wanted the dark haired spiker to carve himself deep in Oikawa’s body, enough to satisfy him for the rest of his eternity, alone.  
  


Soon enough, the setter was raking his nails down Iwaizumi’s tanned back, urging him for more, more of him. He opened his eyes, gazing up at Iwaizumi’s furrowed brow and drinking in the sight, burning it into his eyes.  
  


Iwaizumi moved his hands from beside Oikawa’s head to grip his thighs instead. From his movements, Oikawa assumed he was almost there, and had to resist the urge to beg for more. _Just a little bit more time, please, just tonight_.  
  


However, he gasped instead as Iwaizumi pulled himself out of Oikawa completely.  
  


               “Iwa-cha--!” he started saying before he was swiftly flipped onto his stomach.  Shock had him frozen for a second before Iwaizumi plunging himself back in jump started his brain and Oikawa let out a surprised shout.  
  


His arms scrambled from the awkward position they had landed in and tried to heave himself back up, turning to speak, as his mind was repeating _no, no, not like this. I want to see him, I want to touch him, this is the only time I—_  
  


Fingers wrapped around Oikawa’s hips and suddenly he was pulled back forcefully, seated so deeply on Iwaizumi’s cock that his arms faltered and he fell back onto his chest, a loud moan torn helplessly from his lips.  
  


The fullness from this position blanked out his protests as he writhed on the sheets, sounds leaking from his mouth freely now. After some minutes of blissful pleasure, Oikawa came back to himself as Iwaizumi began slowing down his rhythm.  
  


Trying to catch his breath, Oikawa’s heart jumped at the feel of Iwaizumi pressing himself across Oikawa’s back, breath tickling his ear.  
  


               “You didn’t think your spell actually worked, did you?” the surprisingly slur-free voice of Iwaizumi spoke directly beside his ear.  
  


Oikawa jerked at the sound before his mind caught up a split second later and he paled, body freezing up. “Iwa-chan?” his voice trembled, confused but scared. He tried to lift himself up again, but Iwaizumi’s hands on his forearms kept him pinned down.  
  


               “You’ve been driving me crazy,” Iwaizumi’s voice sliced through the haze of Oikawa’s mind. “I thought I’d actually have to do something about things with how you’ve been dancing around me these last few years.”  
  


_Years…?_ Oikawa thought. Iwaizumi… had known? His body shuddered, feeling as if freezing water had been poured over him at the thought that he’d been caught out long ago, and Iwaizumi had—had been humouring him? “H-Hajime, I’m sorr—”  
  


               “You think I wouldn’t notice all the charms you’ve been placing on me, to ward off supernatural beings, like you were staking a claim, even when _you thought none existed anymore_?” Iwaizumi’s voice was becoming rougher, deeper, and Oikawa trembled; for the first time in his life, afraid. “Thought you were being smart, to mark me in a purely supernatural way, while being ready to surrender against a human.”  
  


               “I—Iwa-chan, I…” Oikawa didn’t know what to say. He didn’t understand what was going on. How did Iwaizumi find out? Was he so out of practice with his magic that Iwaizumi had felt something off from the spells, gone to someone and found out? _He must feel disgusted, that I would claim him that way without his knowledge_. Shame burned through him, realizing – not for the first time – how childish he had been.  
  


               “But you’re not the only one who wants to stake a claim,” the deep growl resounded in his ear, and suddenly Oikawa was aware of a pressure pushing against him. Not magical, nor a physical grip on him.  
  


An animalistic snarl that could not have come from a human startled Oikawa, and his eyes widened at a thought as he turned his head, straining with Iwaizumi’s firm grip still on him to glance behind him, breath catching.  
  


Moonlight streamed into the room, highlighting parts of Iwaizumi’s muscled torso, but his face remained shadowed in darkness. Oikawa’s gaze, however, was locked on the piercing blue eyes pinned on him.  
  


               “A…” _werewolf?!_ Oikawa’s mind supplied in shocked disbelief. The glint of sharp, extended canines brought him back to the present as another growl rumbled through Iwaizumi, and Oikawa’s mouth opened again for a whole other reason.  
  


               “Ah… Iwa-chan? What are—Is that—” The pressure was bearing on him, his entrance, and Oikawa’s heart was thumping loudly in his chest. _A knot?!_  
  


Unsettled, his gaze automatically sought comfort in the form of Iwaizumi but those cold eyes unnerved him. The… _knot_ pushing against him had him choking back a gasp as Oikawa’s hazel eyes began tearing up, conflicting emotions leaving him confused and fearful.  
  


               “ _Iwa-chan_ ,” he whimpered, helpless. “Iwa-chan,” _help me_. He jerked at the feel of a rumbling chest pressing up against his back again, before Iwaizumi released his forearms and slid one hand up to his jaw.  
  


               “Relax, Tooru,” Iwaizumi rumbled, turning Oikawa’s head with such gentleness that the tears in Oikawa’s eyes spilled over as their lips pressed together softly. “You’re mine, aren’t you?”  
  


Oikawa’s eyes blinked open to see Iwaizumi’s own had turned back to their familiar dark hue. A dark gaze that was meeting him head on and pulling Oikawa in, stripping him bare and laying everything out under Iwaizumi’s scrutiny.  
  


               “Yes,” Oikawa admitted in a whisper, “always.”  
  


His breath caught at the smile that graced Iwaizumi’s lips, softening that dark gaze. “And I am yours, always.”  
  


Heart feeling like it was being gripped to tight, Oikawa’s lips stretched in a watery smile. “Really?”  
  


               “Yes,” Iwaizumi’s firm answer blew Oikawa’s defenses away in one fell swoop. “Will you let me in?” he didn’t wait for an answer, instead molding his lips over his beautiful setter’s, tasting him, swallowing his sighs.  
  


One of Oikawa’s hand came up behind him to thread through Iwaizumi’s hair, body relaxing and whimpering as the thick bulge at Iwaizumi’s length slipped in at once. He broke away from the kiss to press his forehead against the sheets, keening loudly at the fullness.  
  


His hands scrambled to grip at the sheets in surprise as the knot began to expand, pushing his already-stretched entrance past its limits as the demon gasped and whined. “Iwa-chan… I can’t—it’s too—”  
  


               “Shh…” Iwaizumi hushed him softly, running warm hands up and down Oikawa’s sides soothingly. “You’re so good. So good for me, aren’t you, Tooru?” He shuffled his position, lifting Oikawa’s hips up with him into a more comfortable position before gently laying them both on their sides.  
  


Warmth spread outwards from inside Oikawa as he was filled and he moaned, flushing at his own lewdness. His cheeks burned as Iwaizumi murmured encouragements and praises in his ear. After a moment, he squirmed against the werewolf.  
  


Trailing a hand down, Iwaizumi wrapped a firm hand around Oikawa’s length and stroked him, burying his nose against the curve of Oikawa’s neck and rumbling in satisfaction as he released, and savored the pleasured trembles wracking Oikawa’s frame.  
  


Oikawa came with a choked sob, spilling over Iwaizumi’s hand before the former spiker raised the soiled hand to his lips and licked at Oikawa’s essence. Already exhausted, Oikawa whimpered at the sight before curling into himself at the feel of Iwaizumi’s seed still filling him up.  
  


His head was turned again by Iwaizumi who rumbled against his lips, “I love you.”  
  


Tears welled up and spilled over hazel eyes, shaky smile soundlessly forming the words, “I love you.”  
  


               “What a terrible face,” Iwaizumi joked softly, lip curling fondly as Oikawa frowned and half-heartedly smacked his thigh.  
  


Turning his head away, embarrassed at the emotional display, Oikawa attempted to wipe at his eyes, sniffling softly. A rough hand grasped his and he was coerced into another deep kiss as they lay together.


	2. Chapter 2

**Notes for the Chapter:**

> So I had this done a while ago on my laptop but never got around to posting it lol... I just added the last tiny bit so soz if it feels out of place.
> 
> Today's also my birthday so you can count this as a bday treat for you guys ;) Enjoy!

Groaning quietly, Oikawa opened his eyes to darkness. A quick glance at the window indicated it was much too early; the sky still dark with only the light of the full moon shining in.  
  


He quietly turned his head to glance behind him. Iwaizumi slept peacefully, breath coming out in silent puffs against the back of Oikawa’s neck. He shivered, feeling oddly hot around the collar.  
  


Silently, he slid his hands down and gripped his hard length, stroking it as he panted against the pillow. Feeling no satisfaction, he squirmed before he brushed against an equally hard object behind him.  
  


Flushing to the tips of his ears, Oikawa daringly reached back and wrapped careful fingers around the werewolf’s length, wriggling as he brushed against the bulge at the base. Shuffling back carefully, he slipped the length between his thighs, the increasing heat wiping away his embarrassment.  
  


Rocking his hips, Oikawa stifled moans into the pillow, resisting the urge to grip Iwaizumi’s hand on his hip by digging his nails into his own thigh. _Not enough, it’s not enough_ , his body screamed. _I want it. Want it inside. I need it inside me._  
  


He reached back and pulled the spiker’s cock from between his legs and pressed the tip against his entrance. As he wriggled fruitlessly, Iwaizumi’s grip on his hip tightened, before hips snapped forward and buried the length inside Oikawa.  
  


               “AH!” the demon shouted in surprise, suddenly filled to the brim, feeling it all the way up in his _throat_. “Iw—ahh, unh…” The heat increased exponentially, blazing a fire within him as he gripped Iwaizumi’s wrist tightly.  
  


A bleary groan sounded before a gravelly voice spoke, “Oikawa?”  
  


               “Iw—Iwa-chan,” he whimpered, hips squirming. “Please, I… I need, Iwa-chan, Iwa-chan,” he chanted mindlessly. “Iwa-chan… what’s—”  
  


Dark eyes cleared and widened, “moon heat,” he whispered, half disbelieving. Iwaizumi swiftly rolled them so that he was atop Oikawa before rising to his knees, bringing Oikawa’s hips with him.

  
The demon tried to push himself up, however his arms felt like jelly and as Iwaizumi thrust sharply against him, his body crumpled, ass remaining lifted by Iwaizumi’s grip.  
  


               “The moon blessing,” panted the werewolf. His arm caged Oikawa’s head, body responding to Oikawa’s own need, _mounting him_. “She is smiling at our union.” He dipped his head, feeling his eyes shifting and canines sharpen. Running a tongue over the junction between the demon’s neck and shoulder, he panted against the skin in silent question.  
  


Despite the all-consuming _need_ burning through Oikawa’s body, his mind remained relatively clear. He shuddered at the intimate touch, knowing there was no question about his answer. “Please,” he nodded, pushing back against Iwaizumi’s hips, keening as the engorged knot slipped into his messy entrance and expanded, locking them together.  
  


The feeling of teeth piercing through his skin ripped a shout from Oikawa’s lips, surprisingly finding further pleasure leaking into him at the point of connection. Coupled with the stimulation to his entrance Oikawa came untouched, whimpering Iwaizumi’s name as his stomach bulged from their second coupling that night.  
  


Oikawa squirmed, silently flushing at how much he enjoyed the feeling of being filled up and held by this possessive, dominant side of Iwaizumi that he’d only recently been acquainted with. Unbeknownst to him as he writhed mindlessly under the haze of pleasure, his delicately casted glamour began to shimmer away, revealing the horns from his head and red seeping into his gaze.  
  


Giving the fresh mark on the demon’s neck a satisfied lick, Iwaizumi pulled back and blinked as he watched the slight transformation of the shuddering form beneath him. He watched as Oikawa panted against the soiled sheets, before turning an unfocused, _red_ gaze in his direction.  
  


               “Iwa-chan,” a breathy voice called to him. Chest rumbling in approval of his mate’s – _his mate_ – utterly vulnerable form beneath him, and the underlying scent of _satisfaction_ rolling off said mate, Iwaizumi pressed Oikawa’s wrists firmly against the sheets as he rolled his hips, knot catching and causing a hitch in Oikawa’s breath.  
  


               “You’re mine now,” he growled, resisting the urge to let too much of his instincts take over despite the full moon shining in strongly through the windows. He leaned down to nuzzle the darkening mating mark on Oikawa’s neck, rumbling in satisfaction.  
  


Said demon weakly raised a hand to thread through Iwaizumi’s hair, and their faces drew close for a light kiss, Iwaizumi’s tongue acquainting itself with the demon’s slightly elongated canines as Oikawa did the same to the werewolf’s sharper pair.  
  


Body sliding in fatigue, Iwaizumi caught him with an arm around Oikawa’s middle and they returned to their previous position, spooned against the bed. Occasionally whimpering at the knot rubbing against his sensitive entrance, Oikawa brought a hand up to his stomach, feeling and marveling at the bloatedness.  
  


Iwaizumi’s hand came around to lay atop his, and they kissed languidly. They both knew nothing would come from the coupling, but with the magic a demon possessed, it was possible.

* * *

They talked, eventually, sitting on the kitchen table the next morning, morning routine surprisingly normal.  
  


               “When did you know?” Oikawa had to ask.  
  


Shrugging, Iwaizumi took a bite out of his mackerel, “from when we were kids. Elementary school, probably. You had an unusual scent on you and when I described it to my parents they knew what you were.”  
  


Oikawa almost dropped his bowl. “Your parents--?! You mean they—I mean, about me—”  
  


               “Yeah my parents are both werewolves. There are still quite a few of us around, just not big communities like you would’ve known I guess.” Another bite and some gulps of his miso soup. “They didn’t see the harm in it; they’d met you a few times after all. My mum said maybe you were feeling lonely. We’ve seen plenty of other werewolves, a few other creatures, but no demons before you.”  
  


Almost choking on his mouthful, Oikawa decided to put a hold on eating breakfast for now. “I…” remembering the events prior to his de-aging stint. “I guess… I mean, I’m almost a millennia and I haven’t met any others either.” Then, remembering a big concern, he unconsciously rubbed against the mark Iwaizumi had left on his shoulder.  
  


               “Iwa-chan… you know I… I can’t—”  
  


Placing his chopsticks down and muttering his thanks for the meal, Iwaizumi glanced over at the unusually anxious demon. “I know you’ll still live for many more millennia. I know that even if we had kids that they’d likely be werewolves because demons don’t procreate demons and that you’d probably outlive them.” He watched the sorrow in those hazel eyes as he strode over and ran his fingers over the mark he’d made.  
  


               “But did _you_ know that werewolves mate for life. And because of that, our bodies adapt and adjust to our mate’s, whether they be ten years older, twenty younger,” he placed his hand over the side of Oikawa’s face, “or live to the end of time.”

* * *

Despite Oikawa’s antsy behavior in the days following, he was surprised to see how unchanged Iwaizumi seemed after everything. However, knowing that Iwaizumi was fully aware of what he was, Oikawa was unexpectedly finding it difficult to drop the act he had been playing for so long.  
  


Every now and then, they’d bump into old friends and Iwaizumi would nonchalantly lean over and drop bombshells of statements which usually left him gaping. One day, after they somehow ran into Ushiwaka while shopping, and Iwaizumi had mumbled, “he’s also a werewolf”, Oikawa’s mind was blown once more.  
  


               “He’s a what?!” he exclaimed, pointing an accusing finger at Ushijima, who simply raised a brow. No doubt he’d heard Iwaizumi’s statement, but his expression meant that he had expected Oikawa to already had known this fact. “Why does it seem like suddenly everyone is supernatural? _How_ do you even know all of this, Iwa-chan?”  
  


Rolling his eyes, Iwaizumi replied, “same as how I knew about you. I could smell it. Idio-kawa you obviously didn’t learn how to tell supernaturals apart despite being ass-old.”  
  


Oikawa gasped scandalously, “ _excuse you_ , Iwa-chan, but _I_ didn’t have parents to tell me all these things!” He turned back to Ushijima who was still there, silently watching. “You better not be telling me now that you were cheating whenever we played,” he accused, “because I worked too hard _without my powers_ to only lose to someone who--”  
  


               “I never cheated,” Ushijima spoke, tone as monotonous and grating as he remembered. “You simply chose the wrong person to rely on,” his eyes slid pointingly to Iwaizumi. “I am superior to Iwaizumi not simply in technique, but as a wolf too.”  
  


Said man growled threateningly and stepped forward, about to argue. However, Oikawa’s hand on his arm calmed him, as the demon spoke instead. “I think you mean that your wolf is just as much of a downer as you, _Ushiwaka-chan_ ,” he watched the other’s eye twitch in annoyance. “Iwa-chan will always be my choice.”  
  


               “I can see that,” noted Ushijima, eyes staring at the mark peeking out of the top of Oikawa’s shirt. His tone seemed somehow even more disappointed in Oikawa than any other time before. Oikawa realized that Ushijima must’ve not only been trying to persuade him not only to be on his team, but consider _him_ as a better partner over Iwaizumi all these years.  
  


               “Ugh!” he shuddered at the thought. “We’re leaving, Iwa-chan. Bye Ushiwaka, hope to never see you again!” with that, he stalked off as quickly as possible, pulling Iwaizumi along with him.

* * *

Oikawa should have known that after having access to such mind-blowing sex all the time – which probably ruined it for him with anyone other than Iwaizumi now – his mind was not exactly _rational_ enough for quick thinking. Otherwise, he would’ve recalled that Iwaizumi’s parents were dropping by for the weekend to visit since Hajime had decided to stay in Tokyo for the holidays due to his part time job here.  
  


Which was how he ended up frozen at the kitchen doorway downstairs the following morning, Iwaizumi’s parents looking up from their breakfast, both pairs of eyes sliding to the raw mark on his neck, bared by the loose-fitting top he’d stolen from Iwaizumi’s room floor.  
  


He didn’t know what was worse – Iwaizumi senior stifling an amused smile in his newspaper or Iwaizumi-mama’s unsurprised smile as she greeted, “good morning, Oikawa-kun. Why don’t you join us for breakfast?”  
  


Not wanting to be rude, Oikawa wordlessly slid into a chair at the table, ears burning in embarrassment as he unsuccessfully tried to stealthily pull up his shirt to cover up any visible marks. He mumbled out his thanks when Iwaizumi-mama placed a hot breakfast in front of him and dug in awkwardly.  
  


               “I suppose congratulations are in order then,” Iwaizumi-papa spoke up, causing Oikawa to choke on his miso soup. “Have to say I was expecting Hajime to at least have called and told us the news.”  
  


               “Uh…” Oikawa replied eloquently. “Sorry? I didn’t…” He jumped in surprise when Iwaizumi-mama placed her hand over his, smiling the same smile he often saw when he would show up at the Iwaizumi household after volleyball practice and be invited to stay for dinner.  
  


               “You know, Tooru-kun, I used to be quite worried what you’d do once you and Hajime would part ways. But when we noticed the… charms,” she shared an amused look with her husband, “that you started placing over him, I knew Hajime would look after you.”  
  


His whole face had to be red by now. _Oh my goooood……._ Oikawa despaired in his thoughts. _His parents knew I’d been secretly marking Iwa-chan as mine from the start!_ If one could die from embarrassment, Oikawa would gladly ask to go right now. Soft hands caressing his cheek and stroking his hair lovingly brought him back out of his thoughts.  
  


               “You’ll take care of our Hajime too, won’t you, Tooru-kun?” Iwaizumi-mama smiled fondly at this boy she’d considered her second son from the moment Hajime had come by speaking of a young child with a weird scent.  
  


Blinking in surprise, Oikawa could only answer honestly, “of course, aunty, I—”  
  


Iwaizumi-mama tutted, placing a finger over Oikawa’s mouth, “call me mum,” she beamed at his stunned expression, pulling him in for a warm hug. As Oikawa slowly wrapped his arms around her, he felt her turn into his neck, nuzzling softly and he choked up as Oikawa realized she was scenting him like a child.  
  


As his sight began to blur, he turned into her own neck, and buried his face in her warmth.

**Notes for the Chapter:**

> Have a great weekend guys!
> 
> Also if any of y'all are interested, feel free to follow my travel insta @ "wandernhunger" or japan insta @ "yininjapan" #shamelesspromo :P

**Author's Note:**

> I am well aware there's probably a ton of errors in the chapter... but it's 2am, I wrote this all in one sitting and hardly gave it a glance over so it's not really been proof-read lol.
> 
> Wow I am so bad at writing sexy times... why am I writing so much talking happening lol idek...  
> Also I feel like I've discovered so many new kinks from my own writing???  
> Sorry :)


End file.
